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Gaia and Gould's Belt

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Gaia and Gould's Belt Gaia and Gould’s Belt Anthony Brown Leiden Observatory [email protected] l The Gaia mission l Summary of the Gaia sky survey l Science performance l Data processing l Catalogue and archive access l Gaia impact on Gould’s Belt research Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.1/26 u ESA Cornerstone mission within Horizon 2000+ programme u Create large and highly accurate stereoscopic map of the Galaxy u Global astrometry concept successfully demonstrated by Hipparcos u Launched on December 19 2013 with Soyuz-Fregat from Kourou u Orbit: vicinity of L2 u Mission duration 5 (+1) years Image credit: Lund Observatory Image credits: NASA/JPL-Caltech/R. Hurt, ESA and ATG medialab Survey capabilities Simulated Gaia sky — Robin et al., arXiv:1202.0132 l Three simultaneous observing G < 20 mag modes 6.0 l Complete to G = 20( V = 20–22) 5.5 l Observing programme: autonomous on-board detection and unbiased 5.0 l 4.5 Quasi-regular time-sampling over 5 Grvs < 17 mag years (∼ 70 observations) 4.0 l Angular resolution comparable to 3.5 HST 3.0 stars/sq degree 10 2.5 Number of objects log 2.0 u 1 billion stars to G = 20 Grvs < 12 mag u 106–107 galaxies 1.5 u 500 000 quasars 1.0 u 3 × 105 solar system bodies 0.5 u tens of thousands of exoplanets 0.0 Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.4/26 Survey capabilities Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.5/26 Number of field of view transits Scan law simulations with AGISLab, image courtesy ESO/S. Brunier Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.6/26 Figure courtesy Xavier Luri, DPAC-CU2 and NASA/JPL-Caltech/R. Hurt Gaia astrometry Parallax relative accuracy horizons (AV = 0:0) 25 M6V M0V M0III K4V G2V K1III 20 B1V 10% B0I 1% V 15 0:1% 10 5 101 102 103 104 105 106 Distance [pc] Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.8/26 Gaia astrometry Parallax relative accuracy horizons (AV = 5:0) 25 M6V M0V M0III 10% K4V G2V K1III 1% B1V B0I 20 0:1% V 15 10 5 101 102 103 104 105 106 Distance [pc] Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.9/26 Gaia astrometry For Galactic disk, with σ$ =$ < 0:3 Figure courtesy Franc¸ois Mignard Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.10/26 Gaia spectrophotometry Photometer l Two channels: 330–680 nm (BP), 640–1000 nm (RP) l Low resolution (∼ 3–30 nm/pixel) prism spectra l Allows derivation of AV , Teff, log g, [M/H], and [α/H] for brighter stars sample sample 40 30 20 10 0 60 50 40 30 20 10 0 3.0 3.0 2.5 2.5 photons) photons) 3 3 2.0 2.0 1.5 1.5 1.0 1.0 BP counts (10 RP counts (10 0.5 0.5 0.0 0.0 400 500 680 900 640 700 800 9001000 λ (nm) λ (nm) Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.11/26 Gaia spectrophotometry 600 0.4 0.3 0 400 A Teff ε ε 0.2 200 0.1 0 0 8 10 12 14 16 18 20 8 10 12 14 16 18 20 G(mag) G(mag) 1.5 1.5 1 1 Logg [Fe/H] ε ε 0.5 0.5 0 0 8 10 12 14 16 18 20 8 10 12 14 16 18 20 G(mag) G(mag) Example of stellar parametrization performance (in this case with SVM). From Liu et al., 2012, MNRAS 426, 2463 Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.12/26 Gaia radial velocities u Slitless spectroscopy in Ca triplet region (847–874 nm) u λ/∆λ ∼ 11 000 20 ] B0V 1 − B5V A0V A5V 15 F0V G0V G5V K0V K1IIIMP 10 K4V K1III 5 End-of-mission radial velocity error [km s 0 9 10 11 12 13 14 15 16 17 V [mag] ‘ Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.13/26 Simulate your own What l Background information on instruments and error modelling l Interpolation tables and formulae l Error variations on sky l Transformations from Johnson, Sloan systems to Gaia photometric system l Will be updated with more information on astrophysical parameter performances, other products from photometry and spectroscopy l Simulated Gaia catalogues (billion objects) will be made available through CDS Where u Go to: www.rssd.esa.int/gaia, look for ‘Science Performance’ button I (or google for ‘Gaia science performance’) u Python implementation at: pypi.python.org/pypi/PyGaia Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.14/26 l Gaia data processing is a Pan-European cooperation I Over 1000 staff years effort since 2006 I Processing power spread over 6 centres Supported through DPAC I participating countries national funding October 2013 I Additional support from 450 members EC Marie Curie and ESF Including: BR CA DPCI DZ ESA IL DPCG US DPCC DPCT DPCB DPCE Data release scenario Figure by Franc¸ois Mignard Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.16/26 Data release scenario l Assumes smooth commissioning and operations! l Each release updates the previous and contains significant new additions l No proprietary period for DPAC Launch December 19 2013 L+22M Positions + G magnitude (∼ all sky, single stars) • Includes more often scanned Ecliptic pole regions • Hundred Thousand Proper Motions (Hipparcos-Gaia, ∼ 50 µas/yr) L+28M radial velocities for bright stars, two-band photometry, and full astrometry (α, δ, $, µα∗, µδ) where available. L+40M full astrometry, orbital solutions for short period binaries, (GBP − GRP), BP/RP Spectrophotometry and astrophysical parameters , radial velocities, RVS spectra L+65M Updates on previous release — including more sources, source classifications, multiple astrophysical parameters, variable star solutions and epoch photometry for them, solar system results End+3yr Everything Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.17/26 Gould’s Belt www.handprint.com/ASTRO/galaxy.html#Gouldbelt Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.18/26 Gould’s Belt Perrot & Grenier 2003 Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.19/26 Hipparcos census of Gould’s Belt l kinematic evidence for physical groups in 12 out of 22 fields l remaining 10 fields had unfavourable kinematics or distance for Hipparcos (e.g., Orion OB1) l Membership (previously <B5) extended to F5, including pre-main-sequence stars in nearest associations l New association in Cepheus: Cep OB6 De Zeeuw, Hoogerwerf, de Bruijne, Brown, Blaauw, 1999 Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.20/26 Gaia — Detailed 3D structure Bouy et al 2014 l All of Gould’s Belt well within reach of accurate Gaia parallaxes I including low mass stars l Example: unravelling of 3D structure of Orion region I Hipparcos provided hints of foreground population in parallax distribution Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.21/26 Gaia — Detailed 3D structure Brown, Walter, Blaauw 1998 l All of Gould’s Belt well within reach of accurate Gaia parallaxes I including low mass stars l Example: unravelling of 3D structure of Orion region I Hipparcos provided hints of foreground population in parallax distribution Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.22/26 Gaia — Kinematics at high accuracy l Transverse motions to better than ∼ 0:5 km s−1 throughout Gould’s Belt l Radial velocities better than 2–5 km s−1 I down to K0V I complementary radial velocity surveys to match transverse motion accuracies l Precise membership of associations I new light on ‘boundaries’ of associations? l Resolving of internal motions I reconstruct birth configuration of associations (Blaauw 1978) I kinematic ages l Tracing runaways to their origins I increase sample Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.23/26 Gaia — Astrophysics of Gould’s Belt l Accurate calibration of stellar structure models I Gaia parallaxes, binary stars, asteroseismology I accurate ages for young stars (MS turn-on and turn-off) I study progression of star formation in Gould’s Belt l Chemical abundances (Gaia-ESO survey) I signatures of star formation by supernova triggering l Mapping the 3D distribution of ISM in and around Gould’s Belt Pecaut et al 2012 I Gaia combined with Planck, HI surveys, etc Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.24/26 Gaia — Astrophysics of Gould’s Belt Lallement et al 2013 Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.25/26 Stay tuned Henk Musterman, Meppel Gaia Survey Performance Data processing Catalogue and archive Gould’s Belt Groningen 2014.04.07 - p.26/26 Extra Material 3D position and velocity of star + satellite orbit, abberation, light bending, etc Direction Gaia–star Vector sun–star Spacecraft attitude Data processing Star position in Centroid stellar image telescope field of view Optical projection on detectors, location/orientation of detectors 1 Gaia spectroscopy u Slitless spectroscopy in Ca triplet region (847–874 nm) u λ/∆λ ∼ 11 000 20 ] B0V 1 − B5V A0V A5V 15 F0V G0V G5V K0V K1IIIMP 10 K4V K1III 5 End-of-mission radial velocity error [km s 0 9 10 11 12 13 14 15 16
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